This application proposes the renewal for 2014-2019 of the Center for AIDS Intervention Research (CAIR) at the Medical College of Wisconsin as an HIV behavioral research Center. CAIR's thematic mission is the conceptualization, conduct, and rigorous evaluation of interventions to prevent HIV infection in communities most vulnerable to the disease; the development of interventions to improve health outcomes among persons living with the disease; and the rapid dissemination of research findings to both the scientific community and public health service provides. The Center's Core structure supports the efforts of an interdisciplinary team of HIV prevention investigators, and CAIR has been highly productive and a strong regional, national, and international resource in the areas of research, training, and service to the scientific and public health communities. CAIR Investigators have made distinguished scientific contributions in the development of HIV prevention interventions for high-incidence populations in the United States, Eastern Europe, and other regions of the world; have advanced the field's scientific knowledge of how to transfer scientific advances to benefit service providers nationally and internationally; and have undertaken vigorous lines of behavioral and social science, methodological, and cost-effectiveness research applied to HIV prevention. CAIR's specific aims during the renewal period are: 1) the development of behavioral, social, and structural interventions that will lead to wide scale public health implementation of recently-emerging biomedical HIV prevention strategies; 2) establishing the effectiveness of multi-level HIV prevention interventions that combine potent behavioral, social, structural, and biomedical interventions to achieve greatest public health impact in reducing HIV incidence; 3) reducing HIV-related health disparities; and 4) serving as a resource that rapidly transforms scientific advances into sustainable public health practice. To support continued excellence in these areas, we propose a structure that brings together interdisciplinary teams and provides resources from the following Cores: Administration Core (Center strategic planning and oversight); Developmental Core (preliminary studies, internal peer review, Center conferences and professional development); Qualitative Core (qualitative and social science support); Quantitative Core (central data management, analysis, and biostatistical consultation); Intervention and Dissemination Core (intervention trial support and technology exchange initiatives); International Core (facilitating international initiatives); and Impact Science Core HIV prevention economic, modeling, and impact analyses). Center Cores synergistically interact, provide added value, and support achievement of CAIR's research aims.